Shell is putting up four Nigerian onshore oil blocks for auction as the oil major focuses on transferring some assets in Nigeria to local companies, Platts reported on Thursday, quoting sources close to the process.

Bids for the four blocks closed on Wednesday and Shell could announce the potential buyers next week.

Nigerian onshore blocks are largely prone to militant attacks, and Shell had sold its 30 percent interest in three oil mining leases in the western Niger Delta, to Seplat Petroleum last year, a Platts release said.

Platts said Shell declined to comment while officials of the bidding companies involved said they were unable to comment because of the confidentiality clause in the negotiations.

According to Platts, local industry analysts have linked the Shell divestment to uncertainty surrounding Nigeria's new petroleum law.